Assigifob



Aug. 9, 1932. E. o. ENGELS 1,871,309

' FLUE SYSTEM FOR HOT GAS HEATED BAKE OVENS Fiied Nov. 8. 1950 A F= I JgJ 1N VEN TOR EUGENE OSCA]? EZVGELS ATTORNEY fiues connecting a supply hea $atente nag. Q, i932 EUGENE OSCAR ENGELfi, OF SAGINA'W, MICHIG, ASSIGNQB T BER 391E it NS COM- rm, INQ, OF SAGINAW, MICHIGAN, A CORWORATION 0F NEW Y6 @VE'NS Application filed November 8, 1930. serial No. 394,227.

This invention pertains to" improvements in bake-oven heating units, each of which comprises a system of gas-tight radiating er and an exhaust header made of sheet metal or other material which transmits heat readily, through which heated gases from a furnace are circulated.

One object of the invention is to provide a flue radiator of the type described, constructed in such a way that the paths of haust flues.

travel of the gases from the inlet to the supply header to the outlet of the exhaust header shall be of the same length through any of the flues.

I further desire to secure such a flue radiator to the oven structure in such a manner that the strains of expansion due to heat shall be distributed over the heater rather than localized in one or two spots.

A further object of my invention is to provide an improved adjustable valve or partition means, within thesupply header, or in both headers, for intercepting the flow of hot gases to certain of the connecting fiues without intercepting the flow through the remainder of said flues, whereby the heat at one or both sides of the heater may be quickly and easily regulated by control means outside of the oven.

With the foregoing objects in view I have designed a gridiron sha ed heatin unit comprising a supply hea er exten ing transversely of the baking chamber, an exhaust header spaced from and approximately parallel to the supply header, said headers connected to their respective supply and exhaust flues at opposite sides of the baking chamber, and a plurality of ducts connecting the headers.

A second novel feature of my invention consists in fixedly'connecting the'above described heating unit to the frame of the oven at two diagonally opposite points only, preferably those pomts where the headers are connected to their respective supply and exsupported, so as to yield freely when the headers and connecting ducts expand or contract.

The rest of the unit is movably movable partitionswhereby the quantity of gas assing through certain of the connecting ues can be reduced or completely out off,

thus controlling the heat distribution laterally of the baking chamber.

Referring to the drawing:

Fig. 1 is a top plan view of one form of heating unit built accordingto my invention.

Fig. 2 is a sectional end view, taken on l'ne 2-2 of Fig. 1.

Fig. 3 is a top plan view of another form of my invention. a v

Fig. 4 is a fragmentary sectional view of the hot gas supply header, taken along line H in Fig. 3.

Fig. 5 is an enlarged fragmentary section taken-along line 5- 5 in Fig. 4, to show the rFneans for adjusting the partitions shown in The construction of my in'vention will now be described. I

Referring to Figs. 1 and 2, numeral 1 designates the oven wall structure, shown in section. The known oven frame is omitted for the sake of clearness. A hot gas duct 2 is installed along one side of the oven chamber from a heater or furnace of suitable type, not shown. At the opposite side of the oven chamber is an exhaust gas duct 3 which conducts the gas which has passed through the flue radiator either to the atmosphere or back to the furnace for reheating.

' Secured to and communicating with the hot gas duct 2 is the supply header 4 of the flue radiator, extending across the oven chamber, but not secured to the opposite wall. An exhaust header 5 is fastened to and communic'ates with the duct 3 and extends transversely of the oven chamber, preferably substantially parallel to the supply header 4;

It is not fixedrelative to the oven wall at the end remote from its connectionwith the cool gas duct 3.

Connectin the suppl header 4 and the exhaust hea er 5 are a p uralit of radiating lines 6 arranged side by side engthwise of I the headers.

At suitably selected places, other than the intake and exhaust ends of the headers, the above described heating unit or flue radiator is movably supported so that the headers 4, 5 and the connecting flues 6 can freely lengthen 5 or shorten as the oven is heated or cooled,

na ly opposite sections of the grid-like assembly. It is apparent that the stresses of -expansion are thus spread over the entire heating unit, and tendency to harmfully strain the joints is practically non-existent. When the headers and ducts are constructed of light-gauge metal, as is the most economical practice, any movement of the parts is comlaterally pensated entirely by the resiliency of the metal of the header.

I will now describe the novel means for controlling the heat of this flue radiator of the baking chamber, that is, from one side of the heating unit to. the other. The overall heat is controlled by suitable dampers in ducts 2 or 3, or in'both, as is well known. By means of movable partitions in the supply headers, the flow of hot gas is diverted to or from ing flues at one side or the other of the assembly.

The control system shown in Fig. 1 cmploys two transverse partitions, 9 and 10 in the supply header 4 and the exhaust header 5 respectively, each movable longitudinally of its header. .In the position shown partitions 9 and 10 permit a free flow of ases through all of the connecting fiues 6; I partition 9 is moved toward the inlet end of header 4 the hot gas is out off from one or more of the fiues 6 at the side of the oven remote from said inlet. As partition 10 is moved toward the outlet end of exhaust header 5, the hot gases are prevented from flowing through those fiues 6 which are at the opposite end of the oven. Thus the heat at either or both sides of the flue radiator can be reduced.

My second and preferred arrangement of movable partitions for controllin the flow of hot gases through the fiues 6 o the radiator is shown in Figs. 3 and 4. The upright partitions 11a and 116 are positioned in the supply header so as to divide the header lengthwise into three passages, each leading from the inlet end of the header to a group of the connecting fiues 6. These partitions are movable laterally of the header for at least a substantial part of their length, so that their ends near the inlet end of the header may be placed against either wall or in contact with eachother. Thus the flow certain of the connectof hot gases to any group of flues 6 can be adjusted or shut off entirely. The inner end of a partition is either hingedto the wall of the header 4, or may be fixed thereto, if the partition is made of light flexible material. The free ends of the partitions 11a and 116 are engaged in pivoted forks 12, which are turned by handles 13 outside of the oven to adjust the position of the partitions.

While I have shown two partitions, 11a and 11b, in the header 4 of Fig. 3, one only, or more than two may be used if desired, without departing from the spirit of my invention. V

This second control system not on] makes possible the diversion of heat from t e radiating flues 6 at either or both sides of the flue radiator, as does the system shown in Fig. 1, but it also makes it possible to reduce the heat in the central section of the radiator, while maintaining the'maximum heat at the sides.

In usual practice, a plurality of these flue radiators is installed in an oven, the number depending upon the size of the oven and the amount of heat required. In either a small or large oven it is simple in operation and economical to build, while it has the advantages inherent in its novel construction. First, it assures an eventemperature in all the radiating fiues, sincethe hot gases must travel a fixed distance from the inlet to the supply header to the outlet into the cool gas duct and no individual flue or groupof fiues 4 will carry more than its due proportion. Second, the'unique method of securing the flue radiator to the oven structure minlmlzes and equalizes expansion stresses within the unit, so that leakage at joints will be very unlikely.' Third, my improved heat control system makes it very easy to quickly correct temperature differences in the oven and to maintain a uniform temperature across the full width of the oven;

Having thusdescribed my invention, what I claim and desire to secure by Letters Patent is: 7

1. In a bake oven, a flue radiator comprising a suppl header connectedat one end to a source of hot gases, an exhaust header substantially parallel to said supply header and communicating with the outside of the bake oven at its end remote from the inlet end of said supply header, a plurality of fiues connecting said supply and exhaust headers, a partition arranged transversely in said supply header and shiftable lengthwise thereof,

for heating gases, a system of fiues for conducting the heated gases from the furnace through the oven including a grid-shaped flue radiator, said radiator comprising a supply header extending transversely of the baking chamber and connected with saidfurnace, an exhaust header substantially parallel to said supply header and connected at the opposite wall of the baking chamber to an exhaust duct, a plurality of flues connecting said supply and exhaust headers, said fi-ue radiator fixed relative to the frame of the oven at-two points only, namely, at the intake end of said supply header and at the outlet end of said ex aust header.

3. In a bake oven, a flue radiator comprising a supply header connected at one end to a source of hot gases, an exhaust header substantially parallel to said suppl header and communicating with the outsi e of the bake oven at its end remote from the inlet end of said supply header, a plurality of fiues. connecting said supply and exhaust headers,

90 and one or more partitions in said supply header dividing the header into a plurality of passages, each passage leading from the inlet to one or more of said flues, each of said par? titions fixed at one end relative to the wall of said sup ly header near the connecting flues and ad]us'table laterally of the header at its other end, whereby the inlet of said passages formed by said partitions can be closed off or increased or decreased in area toregulate the flow of hot gases through the one or more flues fed by each of said passages. 4. In an oven, a heating unit comprising a plurality of radiating fiues each communicating with a sup ly header and an exhaust header, said supp y header fixed to the oven structure. at one end only, and said exhaust header fixed to the oven at the end diagonally across said heating unit from the fixed end of said supply header, means movably sup- 40 porting said unit at other points.

5. In an oven in combination a-fiue radiator comprising a supply header and an exhaust header spaced a art, a plurality of substantially parallel, ues each connected at one end with the supply header and at its other end with the exhaust header, a movable partition within one of said headers and located in the path of movement of gases enterin theheader at one end and flowin into said ues, said partition being adjusta le in the header and capable of being positioned in relation to said stream of gases so as to intercept the flow thereof into certain of saidflues without intercepting the flow through the remainder of the flues.

In testimon whereof, I afiix my si ature. v E GENE OSCAR EN ELS. 

